移动互联网及应用
Big Optical Challenge/Opportunity:Hyperfine Optical FilteringUltra-Low Loss Photonic Waveguides& Resonators Ultra-Low Loss Photonic Waveguides& Resonators Problems: Today’s PIC waveguides have losses closer to Black Paint than to Optical Fibers! Today’s resonator Q’s are well below the predicted limitationsTypical Telecom Fiber Typical High-Index Dielectric and SOI Waveguide Best Ever PLC Waveguide (SiO2-Based) Black Paint Welding Goggles
Projected Limitation of and Achieved Q factor for Crystalline WGM Resonators near 1.5µm 10 10 10 Q factor 10 1014 13 12 11 10 9 8 7
“Best” Fiber
Typical Semiconductor
CaF2 Silica
10-3
10-2
10-1
100
101
102
103
104
105
106
107
108
109
Optical Loss (dB/km) Optical Fiber Planar Waveguides 0.02 dB/µs>200 dB/µs* Table courtesy of Rich Davis, NGST
10 10 10
LiNbO31000
* * **
Al2O3
Ref. L. Maleki, JPL
2000 3000 4000 Wavelength, nm
5000
Opportunity: Opportunity: Orders of magnitude (>102) improvement in optical waveguide& resona
tor loss enables Orders of magnitude (>102) improvement in optical waveguide& resonator loss enables agile RF processing& filtering on a chip (high resolution II/Q optical processors) agile RF processing& filtering on a chip (high resolution/Q optical processors)
“Radical Improvements in Chip-Scale Passive Optical Waveguides& Resonators Are Still To Come” -Steve Pappert, 2007